Self-lowering jack



. F. L. G'ORMLEY SELF LOWERING JACK.

APPLICATIUN FILED MAY 3, I92].

1,395,341. Patented Nov. 1, 1921.

E. 1 a SHEETS-SHEET 1.

F. L. GORMLEY. SELF LOWERING JACK.

APPLICATION FILED MAY 3. I92I.

1,395,341. V v PatentedNov.1,1921. Fi .2,

3 SHEETS-SHEET 2- pmkLaormze F. L. GORMLEY.

SELF LOWERING JACK.

nrrucmdn men MAY 3, 1921.

Patented Nov; 1, 1921.

3 SHEETS-SHEET 3.

.Fig. 5.

UNITED STATES PATENT OFFICE.

FRANK L. GORMLEY, OF BROOKLIN-E, MASSACHUSETTS, ASSIGNOR TO A. O. NORTON, INC., OF BOSTQN MASSACHUSETTS, 'A CORPORATION OF MAINE.

SELF-LOWERING JACK.

Specification of Letters Patent.

Patented Nov. 1, 1921.

. To all whom it may concern:

Be it known that I, FRANK L. GORMLEY, a citizen of the United States of America, and a resident of Brookline, in the county of Norfolk and State of Massachusetts, have invented certain new and useful Improvements in Self-Lowering Jacks, of which the following is a specification.

This invention relates to Screw lifting jacks and particularly to devices of this character which are adapted to lower'under the weight of the load.

The object of the present invention is to provide a.' simple but most effective means for controlling the loweringof the movable member of the jack.

The invention consists primarily in providing frictional means coacting with the lower part of the jack which is inoperative during the lifting operation'but which may be placedin action when it is desired to lower the load.

he invention further consists in means operable by means of a pivoted trigger'for regulating the amount of friction and thereby controlling the speed of lowering.

The invention further consists of certain novel features of construction and arrange- 'ment of parts .which' will be understood readily by reference to the description of the drawings and to the claims hereinafter given.

For the pur ose of illustrating the invention, one pre erred form thereof is illustrated in the drawings, this form having been found togive satisfactory and reliable results although it is to be understood that the various instrumentalities of which the invention consists can be variously arranged and organized and the invention is not limitedto the precise arrangement and organization of .these instrumentalities as herein shown and described except as required by thescope of the appended claims.

Of the drawings: V

Figure 1 represents a vertical section of a lifting jack embodying the principles of the present invention.

Fig.2 represents a vertical section of'the sameon li'ne2, 2, on Fig. '1.

Fig. 3 .represents a horizontalsection of same on line 3, 3, onFig. 1, and r I Fig. 1 represents a horizontal section of same on line 4, 4, onFig. 1.

i i a earche s nd ca e l ke parts throughout the several figures of the drawings.

- ment.

The ram 12 has a vertical slot 13 in one side thereof extending nearly to the bottom of said ram and terminating in a shoulder 14.

The upper end of the standard 11 is provided with a boss 15 in which is mounted a stop member 16, the inner flattened end of which projects into the slot 13 and prevents the ram 12 from rotating about its axis.

Upward movement of the ram 12 is limited by the shoulder 14: coming into contact with the projecting end of the stop member 16.

This stop member 16 is secured in the boss 15 by a pin 17.

The lower end of the ram 12 has secured therein, the nut 18 the thread of which coacts with the thread of the lifting screw 19.

The screw 19 has a bevel gear 20 secured to the lower, end thereof and said gear 20 meshes with another bevel gear 21 formed upon a short operating shaft 22 having mounted on its outer end an operating mechanism 23 of any well-known construction which is provided with means to permit the free rotation of the shaft 22 during the lowering of the load. 7

The lower end of the lifting screw 19 is cone-shaped as indicated at 2 1 and this cone-shaped end 24 rests in a hardened seat 25 set into the closure 26 threaded to the base 10. g

The screw 19 has secured thereto beneath the bevel gear 20, the ratchet wheel 27 and surrounding said ratchet wheel 27 withina cylindrical chamber 28 in the base 10 are two or more segments 29 having curved outer walls adapted to be moved into frictional contact with the cylindrical wall of the chamber 28.

Each segment 29 is provided near one end with a pawl 30 normally pressed outwardly against the teeth of the ratchet 27 by a spring 31.

The teeth ofthe-ratchet wheel 27 and the pawls 30 are so constructed and arranged relativelyto each other that "during the lifting secret on sa save 3, will r de We the ratchet teethbut during the lowering operation said pawls 30 will be engaged by the teeth of the ratchet 27 and force the segments 29 into frictional engagement with the cylindrical wall of the chamber 28.

Superimposed. upon the segments29 is an annular plate 32 surrounding the lower reduced end of said screw 19 and above said plate 32 is a shoe 33 having an upwardly extending pin or stud 34.

This pin or stud 34: is positioned in a lateral recess 35' formed in the standard 11 and said stud extends through the upper wall 36 of said recess.

To the upper end of the stud 34 is pivotally mounted a trigger 37 having a cam projection 38 formed; thereon adapted to coact with the wall 36 to lift the shoe 33 against the tension of the spring 39 surrounding said stud 34.

The handle d0 projecting from the standard 11 is in the same vertical plane as the trigger 37 and prevents it from being moved accidentally; I

The shaft 22 is of such a length that'it may be inserted through the opening in the base 10 and the lateral boss 41 from the standard 11 has a compartment above its centralbore 43 to receive the end of said shaft during its turning movement prior to insertion in the boss 41.

When in place the bushing 13* is inserted into the boss 41 around the shaft 22 and forms a bearing forsaid shaft.

In the operation of the jack. the ram 12 is raised by means of the operating device 23 which through the gears 20, 21 rotates the screw 19 in the nut 18. Y

As this nut 18 is prevented from rotating by means of the stop member 16, it is compelled to move vertically whenever the screw 19 is rotated.

The upper end of thestandard 11 has a cylindrical bearing surface 414: which forms one guide for the ram 12 while the nut 18 coacting withth'e screw 19forms a guide for the lower end of the ram.

The pitch of the thread of the screw 19 is such as to permit the-ram 12 lowering under the load which it is supporting whenever the controlling mechanism is released.

It is obvious thatwhen the shoe 33 is pressed downwardly against the plate 32 and said plate 32 is pressed against the segrotatable with said screw; members surments 29 and the pawls 30 are in engagement with the teeth of the ratchet wheel 27 the ram 12 will be retained in its raised position. -When it is desired to lower the load,1the operator manipulates the trigger 37 and causes the cam 38 to act against the wall 36 and in so doing the shoe 331' is raised from the plate 32 and the pressure of the plate 32 upon the segments 29 is removed. v

When this has been accomplished the screw 19 and ratchet 27 will be rotated in a reverse direction by the downward movement of the non-revoluble' nut 18 and "the teeth of the ratchet 27 will engage the pawls 30 and move the segments 29 therewith, the outer walls of said segments 29 being forced into frictional engagement with the cylindrical wall of the chamber 28 and thereby preventing the ram 12 from lowering too rapidly.

Should the speed of lowering be too great the operator by manipulating the trigger 37 permits the shoe 33 to be lowered under the tension of the spring 39 and thereby apply sufficient friction between the shoe 33- and plate 32 and between said plate 32 and the segments 29 to further retard the speed of lowering of said ram 12. I

It is self evident that by means of this device any degree of friction may be attained between the shoe 33, theplate 32, and the segments 29 and in this manner the speed of lowering may be easily regulated.

The pawls 30 are each provided with a semi-cylindrical head 45 positioned in a cylindrical recess 46 in each segment member 29 the wall of said recess 46 extending around said head sufliciently to prevent the pawl 30 from moving endwise and being jammed against the wall of the depression d7 in which its free end swings about the center of the head 45.

It will be noted that the lateral boss 41 is termed integral" with the standard 11 and so-constructedas to permit the insertion of thus greatly simplifying the construction of the jack.

The number of operating parts are re- .duced to a minimum and consequently the liabilityot thejack to get out of order is reduced to a minimum. v

It is believed that the operation and many advantages of the invention will be understood without further description.

Having thus described my invention, 1 V7 claim:

1. The combination of a casing having a cylindrical chamber; .a, rotatable lifting screw; a movable ram provided with a screw thread coacting with said screw; a ratchet the cylindrical wall of said chamber; a

pawl on eachmember coacting with said ratchet; and operating, mechanism for. rotating the screw during the lifting operation.' y 1 2. The combination ofa casing having a cylindrical chamber; a rotatable lifting screw; a movable ram provided with a crew thread coacting with said screw; a ratchet rotatable with said screw; members surrounding said ratchet and having peripheral walls adapted to contact frictionally with the cylindrical wall of said chamber; a pawl on each member coacting with said ratchet;

means preventing the rotation of said ram;

and operating mechanism for rotating the screw during the lifting operation.

3. The combination of a casing having a cylindrical chamber; a rotatable lifting screw; amovable ram provided with a screw thread coacting with said screw; a ratchet rotatable with said screw; members surroundin said ratchet and having peripheral walls adapted to contact frictionally with the cylindrical wall of said chamber; a pawl on each member coacting with said ratchet; means preventing the rotation of said ram and limiting its upward movement; and operating mechanism for rotating the screw during the lifting operation.

4. The combination of a casing having a cylindrical chamber; a rotatable lifting screw; a movable ram provided with a screw thread coacting with said screw; a ratchet rotatable with said screw; members surrounding said ratchet and having peripheral walls adapted to contact frictionally with the cylindrical wall of said chamber; a. pawl on each member coacting with said ratchet; an annular plate superlmposed upon said members; means for forcing said plate into contact with said members; and operating mechanism for rotatlng the screw during the lifting operation.

5. The combination of a casing having a cylindrical chamber; a rotatable lifting screw; a movable ram provided with a screw thread coacting with said screw; a ratchet rotatable with said screw; members surrounding said ratchet and having peripheral walls adapted to contact frictionally with the cylindrical wall of said chamber; a pawl on each member coacting with said ratchet; an annular plate superimposed upon said members; means for forcing said plate into contact with said members; a device for controlling the operation of said. forcing means; and operating mechanism for rotating the screw during the lifting operation.

6. The combination of a casing havin a cylindrical chamber; a rotatable lifting screw; a movable ram provided with a screw thread coacting with said screw; a ratchet rotatable with said screw; members surrounding said ratchet and having peripheral walls adapted to contact frictionally with the cylindrical wall of said chamber; a pawl on each member coacting with said ratchet; an annular plate superimposed upon said members; a shoe normally coacting with said plate; means for separating said shoe and plate; and'operating mechawith the cylindrical wall of said chamber;

a pawl on each member coacting with said ratchet; an annular plate superimposed upon said members; a shoe normally coacting with said plate; a stud thereon; a spring surrounding said stud; means for raising the shoe against the tension ofsaid spring; and operating mechanism for rotating the screw during the lifting operation.

8. The combination of a casing having a cylindrical chamber in its base; a rotatable lifting screw; a movable ram provided with a screw thread coacting with said screw; a ratchet rotatable with said screw; members surrounding said ratchet and having peripheral wall adapted to contact frictionally with the cylindrical wall of said chamber; a pawl on each member coacting with said ratchet; an annular plate superimposed upon said members; a shoe normally coacting with said plate; a stud thereon; a spring sur-' rounding said stud; a pivoted trigger for raising the shoe against the tension of said spring; and operating mechanism for rotating the screw during the lifting operation.

9. The combination of a casing having a cylindrical chamber in its base; a rotatable lifting screw; a movable ram provided with a screw thread coacting with said screw; a ratchet rotatable with said. screw; members surrounding said ratchet and having peripheral walls adapted to contact frictionally with the cylindrical wall of said chamber; a pawl oneach member coacting with said ratchet; an annular plate superimposed upon said members; a shoe normally coacting with said plate; a stud thereon; a spring surrounding said stud; a trigger pivoted to said stud and provided with a cam projection for raising the shoe against the tension of said spring; and operating mechanism for rotating the screw during the lifting operatlon. I V

10. The combination of a casing having a cylindrical chamber in its base; a rotatable lifting screw; a movable ram provided with a screw thread coacting with said;

screw; a ratchet rotatable with said screw; members surrounding said ratchet and hav ing peripheral walls adapted to contact frictionally with the cylindrical wall of said chamber; a pawl on each member coacting with said ratchet; an annular plate superimposed upon said members; a shoe normally coacting with said plate; a stud thereon; a spring surrounding said stud; a trigger pivoted to said stud and provided with a cam projection; a handle to said casing extending around said trigger for raising the shoe against the tension of said spring; and operating mechanism for rotating the screw during the lifting operation.

11. The combination of a casing having a c lindrical chamber a movable ram in said casing; rotatable means for raising said ram; a ratchet secured to said rotatable means; members surrounding said ratchet and having peripheral walls adapted to contact frictionally with. the cylindrical wall of said chamber; and a pawl on each member adapted to coact with said ratchet during the lowering operation.

12. The combination of a casing having a cylindrical chamber; a movable ram in said casing; rotatable means for raising said ram; a ratchet secured to said rotatable means; members surrounding said ratchet and having peripheral walls adapted to contact frictionally with the cylindrical wall of said chamber; a pawl on each member adapt ed to coact with said ratchet during the lowering operation; an annular member superimposed upon said members; and means for producing pressure upon said annular memher to create friction between said members and said annular member.

'13. The combination of a casing having a cylindrical chamber; a movable ram in said casing; rotatable means for raising said ram; a ratchet secured to said rotatable means; members surrounding said ratchet and having peripheral walls adapted to contact frictionally with the cylindrical wall of said. chamber; a pawl on each member adapted'to. coact with said ratchet during the lowering operation; an annular member superimposed upon said members; means for forcing said annular member into frictional contact with said members; and a manually actuated device for controlling said forcing means.

1 1. Thecombination of a casing havinga cylindrical chamber; a movableram in said casing; rotatable means for raising said ram; a ratchet secured to said rotatable means; members surrounding said ratchet and having peripheral walls adapted to contact frictionally with the cylindrical wall of said chamber; and an oscillating pawl so positioned in. each member as to prevent end movement thereof and adapted to coact with said ratchet during the lowering operation.

15. The combination of a casing having a cylindrical chamber; a 'mov'able ram in said casing; rotatable means for raising said ram; a ratchet secured to said rotatable means; members surrounding said ratchet and having peripheral walls adapted to contact frictionally with the cylindrical wall of said chamber; and a pawl having a semicylindrical end positioned in a cylindrical recess in each member and adapted to be moved. about its pivot to engage said ratchet during the lowering operation.

Signed by me at 294 Washington St, Boston, Mass, this th day of April, 1921.

Y FRANK L. GORMLEYL Witnesses I WALTER E. LoMBAnn, NATHAN C. LoM ARn. 

